Add purgelock management command. Closes GitLab issue #221.

Signed-off-by: Roberto Rosario <roberto.rosario.gonzalez@gmail.com>

mayan/apps/lock_manager/backends/base.py

@@ -0,0 +1,15 @@
+from __future__ import unicode_literals
+
+
+class LockingBackend(object):
+    """
+    Base class for the lock backends. Defines the base methods that each
+    subclass must define.
+    """
+    @classmethod
+    def acquire_lock(cls, name, timeout=None):
+        raise NotImplementedError
+
+    @classmethod
+    def purge_locks(cls):
+        raise NotImplementedError